Which is not a common nonmetallic mineral? sodium, aggregate, garnet, or limestone?

the chemical element of atomic number 11, a soft silver-white reactive metal of the alkali metal group. sodium i think.

sodium

Explanation:

Non-metallic minerals are the minerals which contain non-metals. Like non-metals these minerals do not exhibit luster and they break off easily. Examples of non-metallic minerals include limestone, aggregate, and garnate.

Sodium is an alkali metal, which is highly reactive and silver white in color.

i'm thinking (a) to keep sand in place; ////////////

explanation: a sand fence or sandbreak, like a snow fence, is used to force windblown, drifting sand to accumulate in a desired place. sand fences are employed to control erosion, sand dune stabilization, keep sand off roadways, and to recruit new material in desert areas.